Biopellet Reactor: Tuning

[DamonG]

Ok it's 3am but I had to, reefers get it:

I wanted to see if the manifold feed setup I have is what may be restricting my flow.
It was suggested that this eheim would do 3000gph. Granted it is serving dual purposes on the BPR, one is to feed the reactor, the other is provide churn or tumble and effluent, so a bit less than 3000gph expected

Measured current effluent again and confirmed: effluent = 1860mL/min = 29.5 gph = 707 gpd

So I take the feed line off my manifold and put it directly in the sump, premise being the manifold is the culprit that eliminating the manifold would allow me to see the flow rate

Effluent rate with manifold eliminated?
1000 mL/min = 15.85gph = 380 gpd

We were expecting more right? So what gives, is the flow really resrticted to get 29.5 gph? Should I inspect the pump?

Yes, something is up with it definately. Not putting out flow nearly where it should be. I would take the pump off and play with it by itself.

I haven't measured my effluent with a beaker personally on this system, but I will say that, with 1/4 of the way open on the blue, it is well over what I have observed for 55gph. I don't know if that helps at all

 

[gdemos]

FWIW, comment from RD is:
"500gpd is what you should get for an average. But since you want it working a little bit harder I would say keep it at that 700gpd for now"

they are also trying to sell me a skimmer of course

So i will inspect the pump, likely revert back to the manifold as this gives me the ability to boost and control feed more precisely, and see how much i can push through there.

i know gpd can be mistyped to gph, etc. but if RD is saying 500 gpd... 21 gph, that hasn't proven to be effective for me.

 

[gdemos]

here's an excerpt from a post by Avast Marine, seems that in a True Recirc Reactor, the 38-55gph in a 200g system (not far from my setup), is appropriate:

So what is the optimal flow rate for a recirculating biopellet reactor? First we have to define the goals, in this case the first goal is to achieve the longest possible contact time with the tank water and the media. The second goal is to make sure all of the water comes in contact with the media during an average day.
To determine the formula for this we will look to the works of P.R. Escobal who is one of the most well respected scientists and engineers with regards to modern aquarium systems. In his reference manual, Aquatic Systems Engineering he provides us with the following equation to solve this problem:

T=a(G/F)

where:
T= time, the number of hours for all water to pass through a given device
F= flow rate through the device (GPH)
a= Purity coefficient. This is a constant based on the percentage of total tank water that you want to pass through the device.
G= Total system volume in gallons.

Lets look at the Purity coefficient in more detail as that is the one most willl likely not understand in the formula. This is a fixed number from another more complex formula but the easiest way I can explain it is something like this:

The first number represents the constant and the second number represents the percentage of water filtered during the defined time (T).

4.6 = 99%
6.9 = 99.9%
9.2 = 99.99%

Next, lets look at time (T). We are going to use 24 here, for 24 hours.

Now we have enough information to solve the equation. We are going to use a 200g system running 1 liter of biopellets as our example and a purity coefficient of 6.9


T=a(G/F)
24=6.9(200/F)
F=6.9(200/24)
F=57

Flow rate = 57gph.

If we solve the above using the 99% and the 99.99% coefficients we come up with 38gph and 77gph respectively. We consider this the ideal "range". The conclusion of all of this is that we can see that if we want the longest possible contact time combined with highest percentage of water flowing through the media, the optimal flow rate is going to be between 38-77gph. Our advice would be to not get hung up on the "exact" number but instead shoot for something in this range.

So why a ricirculating biopellet reactor? You simply cannot fluidize 1 liter biopellets with a 38-77gph flow rate. This means you are not maximizing the contact time with the media to it's true potential.

I present the following scenario and equation:

Same 200g tank running 1 liter of biopellets at 350gph to achieve fluidization.

T=a(G/F)
T=6.9(200/350)
T=3.94
Time=3.94 hours.

So you still achieve the same 99.9% of water going through the reactor but it happens in 4 hours instead of 24.

Conclusion: A recirculating biopellet reactor increases contact time with the media by 600% during the course of a day. This maximizes the effectiveness of the media to it's true potential without clumping or sacrificing contact time.

 

[DamonG]

Lol, yes that is true and i have their recirc modification on my gfo reactor. However, when your trying to set it up and get it running right at first, and things are not going right, instructions of that sort are kind of like an engineer and his project :may be good for the masses, but practical application can and usually is far from the instructions.

Fir example, yes, "i" can do that to mine, and it indeed may be "close" to where it eventually ends up, but that's only because mine is running right. Right now, yours isn't, so your trying to isolate the problem. So you have to do some experiments. Then, once you know what is going on, then, and only then, can you sort of go back to the standard.

And honestly, because every system is different, and your not using an avast reactor, you may be no where near that theoretical number. Just being honest.

But.. And the big but is :No matter where you end up, your pump should be pumping a ton more water than that wide open. It may not be needed to be wide open, and more than likely will not, but it still should function right "if you need it to".. And from what your saying, it's not..

 

[DamonG]

FWIW, comment from RD is:
"500gpd is what you should get for an average. But since you want it working a little bit harder I would say keep it at that 700gpd for now"

they are also trying to sell me a skimmer of course

So i will inspect the pump, likely revert back to the manifold as this gives me the ability to boost and control feed more precisely, and see how much i can push through there.

i know gpd can be mistyped to gph, etc. but if RD is saying 500 gpd... 21 gph, that hasn't proven to be effective for me.

But, as they are saying "keep it at".. Lol, that's your max.. They are talking about throttling it back and not all the pump can do.

And what your saying as far as" it's not enough for your system "is exactly right. They may say that, and in theory and all things being equal, yes, it probably would be fine. But, we all know nothing is equal with these systems and these tanks. Along with the equipment that is being used on them.

Now, lol, I love my dynamics equipment and I have no qualms recommending it, but, the skimmer really isn't going to help your situation. It really is an issue with a "different piece of equipment" that, yes, if it were working right (the pellet reactor that is), i honestly think you would see what they meant, but then, I don't know everything about your skimmer. However, from remembering your issues with it, I'm gonna say that maybe it's good your not seeing the full effects of the reactor, as it does really "crank" on a skimmer and test it.

But, if you doubt it, just buy another /extra pump and hook it up. I think you might be shocked at the performance difference.. I have an extra Sicce 1.5 for my reactor just in case, along with extra return and axillary pumps.. Just in case..

 

[Aqualund]

FWIW, comment from RD is:
"500gpd is what you should get for an average. But since you want it working a little bit harder I would say keep it at that 700gpd for now"

I don't know why they are saying this...like...I can't fathom the motivation behind keeping you in a parameter that will prevent successful removal of nitrates.

just pop a feed pump on the intake to the reactor...push around 200-300gph and let er' run.

 

[gdemos]

Beyond their interest in selling me a skimmer... The suggestion of how their average is 500gpd is that this reactor with some 50oz of pellets, it is the pellets primarily that lessen the throughput flow. So I bumped up the manifold feed and now get timing 1020 gpd up from 700. Beyond some additional tweaking of the manifold I will like you say have to get a feed pump.

I inspected the pump and lines and although a little film of slime all was pretty darn clean. Given the placement of my reactor on a shelf above the sump, this too plays a part in a lesser flow.

They also are saying in a recirc rx it's all about contact time and less about effluent. Further "in not sure those gaskets will hold up at something like 7000 gpd". Not exactly reassuring!

My next move is to perhaps bypass the manifold and source feed closer to the main return line as opposed to the branch; or as Aqua says get a standalone feed pump.

 

[SchnitzelReef]

There is no way that reactor can work correctly with a 700gpDay output. Especially with all those fish and feeding 12 cubes/day. Should be something like 200 gpHOUR. I've been running BPs for almost 3 years. I have my effluent plumbed to the same chamber as my skimmer, near the intake. Also your skimmer needs to be skimming efficiently for BP to work correctly. That skimmer works great, I had a SRO xp3000. BUT u have it skimming WAYYY too dry. Pull the effluent line out of the skimmer intake, and just let it come out near the intake of the skimmer. Then tune your skimmer so that it is skimming correctly.

Whatever they told you to do obviously isn't working, try what I just said and wait a few days. Also stop dosing MB7, it's not necessary. If there is nitrate and phosphate present in your system, those pellets will pull em out....just make sure that skimmer is adjusted correctly.

 

[gdemos]

Easy fix to simply direct effluent near intake as opposed to plumbed directly
I'm looking at sicce syncra 3 as a feed. It should accomplish flow I need given a few feet of head.

Could also look to feed off main return with a larger diameter feed line

I have given up listening to manufacturer recommendations as it seems that everyone else says more flow. RD insists no one else running at such high flow is running a true recirc reactor and that they are calculating flow incorrectly.

Has anyone pulled their effluent line and truly calculated flow?

 

[gdemos]

http://www.youtube.com/watch?v=GWqZ1LkTtwk

 

[SchnitzelReef]

http://www.youtube.com/watch?v=GWqZ1LkTtwk

From my experience, I would slow the tumble down a little bit. Not sure if someone recommended to tumble the pellets faster, but the way you had it before is how I have mine tumbling. In that video, they look like they are tumbling too hard. When that happens, you can expect the dreaded cyano. (Not always cyano, but 9/10 in my tank).

Any chance you can get a video of the effluent line OUT OF WATER? That way I can see how much water is coming out of the line? Personally I think you will be fine with running the reactor off the manifold. Unless it's trickling out. A quick video should clear this up quickly

 

[Aqualund]

From my experience, I would slow the tumble down a little bit.

Yes I was going to say just this. All you need is a tumble that is sufficient to fluidize the pellets, any more and you will be pulverizing the pellets way too quickly.

As for RD saying no one is running more than their recommended dose? Well okay, maybe a system that is finally at <.05ppm NO3 is dialed back to 700gpd...but even this would be very rare as a sufficient dose.

I can show pictures and videos of about 10 systems I run personally...and and the 50+ videos from customers doing 200+ gph as normal operating range (on big systems with heavy loads).

It would be like hooking up a 5 gallon pail to your plumbing and dosing a gallon of vodka into it daily...but only letting the output from the bucket dribble out. OF COURSE there will not be enough carbon going into the display to make a difference!

But also I want to be clear...this 200gph you'll be shooting for is merely for reducing your nitrates. You might find that once you're in a good range...50, 25 or 10gph might be the correct operating rate. Every system is different.

 

[gdemos]

Here goes. Unless I bush up the plumbing out of reactor (larger effluent line than current 1/4" line) Then feed pump is only way I can get an increased flow

Here's an updated video. After taking this film I got a more accurate effluent flow rate calculation and I'm at equivalent of 49.8 gph as is

http://www.youtube.com/watch?v=RbTEnbosRnA

 

[Aqualund]

Yeah everything right now looks really good. I would run it like this for a couple of weeks. You will definitely see a reduction.

BTW I like how you operate everything. very clean and fastidious.

 

[gdemos]

Thanks for the compliment! Most of all thanks all here for the insight and support. This build has been a compilation of my own compulsive sense for order and a pro designer. All along I try to be selective where I get my advice from and I appreciate the collaboration and help. Let's hope a few days at this run rate brings levels in line!
Greg.

 

[gdemos]

Ok i got skimmer humming well with effluent near intake but not plumbed directly. All was good. So after 10 hours of this I plumbed effluent direct to intake maybe at 3pm yesterday and all was good

8am all looked good. 9am I look at tank and see cloudy water

Slight flood in basement due to overflowed skimmer, cloudy water due to kalk top off. Figure I lost 7g water thankfully top off with 1.025 and not much salinity changed in the net result.

So, what's the verdict does the direct plumb cause the skimmer to freak out at any random interval? Am I best off keeping effluent adjacent to intake and not plumbed direct? Does such setup increase risk of cyano due to biofilm in system and cycling?

 

[SchnitzelReef]

Ok i got skimmer humming well with effluent near intake but not plumbed directly. All was good. So after 10 hours of this I plumbed effluent direct to intake maybe at 3pm yesterday and all was good

8am all looked good. 9am I look at tank and see cloudy water

Slight flood in basement due to overflowed skimmer, cloudy water due to kalk top off. Figure I lost 7g water thankfully top off with 1.025 and not much salinity changed in the net result.

So, what's the verdict does the direct plumb cause the skimmer to freak out at any random interval? Am I best off keeping effluent adjacent to intake and not plumbed direct? Does such setup increase risk of cyano due to biofilm in system and cycling?

Maybe some skimmers have no problems with overflowing when effluent is run directly the intake, but your RO skimmer didn't seem to like it. Keep it this way for a couple weeks and see what happens. Like I said earlier, I ran my effluent to the same chamber as the skimmer, directed near the intake on the skimmer pump and it worked great for years. (I recently took my pellets offline to upgrade BP reactors) The key is having an efficient skimmer and making sure it's tuned correctly. Does that skimmer overflow often?

Also I noticed it looks like u have a cap on one of the intake silencers...what's the reason for that?

 

[SchnitzelReef]

Yeah everything right now looks really good. I would run it like this for a couple of weeks. You will definitely see a reduction.

BTW I like how you operate everything. very clean and fastidious.

I agree. Let those pellets do what they do. I wouldn't mess with effluent flow or tumble. Sometimes people tend to constantly tinker with things, and it can backfire. Let the equipment work and stop making changes.

 

[gdemos]

I do try to limit tinkering and certainly avoid big changes when I do. Bare in mind I'm still fish only in this system so I am fortunate to have some leeway in adjustments

have previously had exterior room air line connected to the skimmer silencer. I began to experience problems and have terminated that line. The skimmer air silencer has two inlets for air. I can cap or leave open.

Overflows occur if I try to get wet skim. Challenging to find the balance. And of course the overflow happens long after any adjustments are made so it is rare for me to catch the overflow at the instant. This is why I have had it on the dry side.

Not to speak too soon but... American marine monitor reading 6 NO3-N down from yesterday's 23.

Could it really be happening?

 

[gdemos]